Orthogonal frequency division multiplexing (OFDM) is a method of multi-carrier digital communication where wideband information data is distributed across many narrow-band “subcarriers” in the frequency domain. Because each individual subcarrier is a narrowband sinusoidal wave, it can be transmitted with less distortion caused by inter-symbol-interference over multipath wireless fading environment. The original information can be recovered at the receiver without a complex equalization process, and is robust in a multipath propagation environment.
Orthogonal frequency division multiple access (OFDMA) is a method of multi-user digital communications, wherein each user utilizes an allotment of the available sub-carriers for their individual communication. The fundamental operation and advantages of OFDMA systems is similar to that of OFDM systems in a multipath wireless propagation environment. So the terms OFDM and OFDMA are used here interchangeably.
An accurate channel estimation in an OFDM receiver is important for the recovery of the transmitted information data at the receiver. If the receiver makes a significant error in its channel estimation, the original modulation symbol can be decoded in error because each subcarrier in the OFDM symbol is multiplied by fading coefficients that have different amplitudes and phases. This is especially true for higher-order 16-QAM and 64-QAM modulation, which are widely used to transmit high data rate signals. However, the accuracy of channel estimations depends on current conditions of a multipath signal propagation environment.
Thus, there is a need for a device and method for performing a channel profile estimation to improve the accuracy of channel estimations.